Atrial fibrillation is a growing health and economic burden worldwide. It is the cause of a quarter of all ischaemic strokes and yet many people are not aware that they have the condition. The Screening and Optimising Stroke Prevention in Atrial Fibrillation (SOS-AF) service was set up at Cambridge University Hospitals NHS Foundation Trust to tackle the issue. Demonstrating excellent best practice, the SOS-AF service is a winner in the AF Association Healthcare Pioneers Report 2019.

Find out more about this project by watching our YouTube video below.

SOS AF video screenshot

Cambridge University Hospital in 2014-15 showed a substantial increase in the burden of AF in general medical admissions with a prevelance of 15% in a population with a median CHA2DS2VASc of 4.4. Only 60% of patients with known AF were on anticoagulation on admission and only 38% of those with newly-diagnosed AF left hospital anticoagulated.

Data from the Sentinel Stroke National Audit Programme (SSNAP) in 2016-17, which measures the quality and organisation of NHS stroke care, demonstrated that:

  • In our region 22% of all stroke admissions had a prior diagnosis of AF, and 49% were not on anticoagulation prior to stroke.

The goal was to identify and anticoagulate all appropriate patients with AF, thereby improving quality of care and reducing the huge healthcare burden of AF-stroke.

SOS-AF provides in-hospital AF screening of all medical admissions, ensuring that previously undiagnosed AF is not missed and that every AF patient is risk-stratified with regards to appropriate stroke prevention. The vision is: “No one with known AF should suffer an avoidable AF-related stroke.”  The service offers specialist advice to hospital teams and primary care regarding initiating anticoagulation in appropriate patients and focuses on patient empowerment through education. Consisting of 4 stroke specialist doctors and 2 specialist stroke prevention nurses, it provides: 

  • Screening to improve detection of AF – secondary care is an important yet under-utilised place to screen individuals at high-risk of cardioembolic stroke. Every patient admitted to general medicine is screened for AF using electronic medical records and ECG.  The service also accepts referrals to the stroke prevention clinic or multi-disciplinary team (MDT) from medical teams, GPs, and cardiology services.
  • Optimisation of stroke prevention – all AF patients are risk-stratified using a holistic approach by the SOS-AF team which considers an individual’s stroke-risk. The patient and medical teams are involved in all decision-making.
  • Support – increasing AF awareness in the community, patient education and supporting primary and secondary care in understanding and overcoming barriers to anticoagulation.

Current data shows the burden of AF in acute medical admissions has risen further to 21.3%, and 71% of patients with known AF are admitted on anticoagulation. In the first 12 months, we have screened 14,979 inpatients and identified 402 new AF cases with the following results:

  • 401 patients were anticoagulated following our advice to medical teams, GPs, or in the clinic. This includes changes to inappropriate anticoagulant choice or dose where sub-optimal AF-related stroke prevention therapy was identified.
  • This equates to the prevention of 16 AF-related stroke and 8 deaths (Number needed- to treat (NNT) with anticoagulation to prevent one AF-stroke is 25).
  • Calculations using the median length of stay of a cardioembolic stroke in the trust (15.9 days) equates to reducing 254 bed days annually, a saving to the Trust of £89,000.
  • We advised medical teams and GPs not to anticoagulate 158 patients where, on balance, the risks outweighed the benefits with clear guidance for future care.

Commitment to community support has included:

  • Patient education days at GP surgeries focussing on AF and anticoagulation
  • Primary care workshops on overcoming barriers to anticoagulation
  • AF awareness public engagement events

In the year, the SOS-AF service has prevented approximately 16 cardioembolic strokes.

  • The project was shortlisted for a BMJ Award.
  • The project has been featured as best practice in the National Institute for Health and Care Excellence (NICE) Shared learning database.
  • It has been featured on the Anticoagulation Foundation website.

“Following the SOS-AF talk I will be more pro-active in my anticoagulation management with my AF patients. The talk has changed the emphasis placed on HAS-BLED, falls risk and paroxysmal AF. I have since reviewed patients who were not previously thought suitable for anticoagulation, and as a result a number are now protected from stroke.” Cambridgeshire GP

“I am very grateful for the stroke prevention service identifying my risk of stroke. My AF was explained very clearly, and I felt able to make the decision to start blood thinning tablets. I feel safe now I am protected. I was also grateful that the nurse saw me on a day I was already visiting the hospital. He also arranged my 24-hour tape to be fitted while I was there too, which saved me two extra visits to the hospital.” Patient reviewed by the SOS-AF service at Cambridge University Hospital

Funding for this project was initially provided through the AHSN Network’s partnership with the BMS-Pfizer Alliance for Stroke Prevention in AF Competitive Grant Scheme.

© Eastern AHSN